As an avid indie game and bullet hell fan, I don't say this lightly: Star of providence is one of the best games I've ever played.
There's some unique stuff I really like - weaving between bullets is crazy satisfying, because your hitbox is a tiny little dot in the center of your ship. The true final bosses pull zero punches and acknowledge the fact that you've just saved up all your resources to beat them; they are VERY difficult. All items in the game have a use, even when you're full on ammo and health. The powerups on the different floors (conduits) are well balanced and fun to use. Weapons in this game all feel completely unique, with tons of different "keywords" that totally change their function, as well as rare artifact weapons. Also the bosses are SUPER fucking cool
The thing that really hooked me, though, is the extremely cryptic lore. I pushed through absurdly difficult challenges because I wanted to know more about it. I just completed my first S rank run as of writing this - and I can say that everything was tied together at the very end.
Seriously, play this game, it's so worth it